ABSTRACT
Melanocytes are melanin-producing cells located beneath basal cells and squamous cells in the epidermis. The melanin is a pigment that gives the skin its natural color. Upon exposure to the sun, melanocytes produce additional pigment to protect the nucleus of keratinocytes from ultraviolet (UV) damage, rendering the skin to tan, or darken. Risk factors for melanoma include a fair complexion (e.g., fair skin that freckles and burns easily, does not tan, or tans poorly; blue, green, or hazel eyes; and red or blond hair), exposure to natural sunlight (blistering sunburns) or artificial sunlight (tanning beds), small moles, freckles, and family history of unusual moles or melanoma. Clinical warning signs for melanoma include change in size, shape, color, or elevation in a preexisting pigmented lesion (mole); itching or pain in a preexisting mole; and development of new pigmented lesions. Surgery is curative for early-stage melanoma, but is less effective for melanoma that metastasizes to distant lymph nodes or organs.
